1. Field of the Invention
The present invention relates to a method of inspecting a semiconductor device by which an inspection can be performed under proper inspection conditions on a semiconductor substrate manufactured in a desired manufacturing process of a semiconductor device and an apparatus thereof and, more particularly, to a method of finding an inspection condition in an inspection apparatus, by which a proper inspection condition is selected to a sample to be inspected and a method of selecting an inspection apparatus to a sample to be inspected.
2. Description of the Related Art
An inspection condition in an inspection apparatus have been conventionally determined by the steps: inspecting a sample for calibration, which has bumps and dips equivalent to actual foreign particles and defects, under a certain inspection condition; analyzing the state of detection of the bumps and dips; in the case where the results of the analysis are not good, inspecting the sample for calibration again under a changed inspection conditions; and the inspection of the sample and analyzing the state of detection of the bumps and dips; and repeating these procedures under different inspection conditions until the results of analysis become satisfactory. In this way, a proper inspection condition 1 is set.
Here, in Japanese Unexamined Patent Publication No. 9-306957 (related art 1) is disclosed a technology for making an identity judgment on a foreign substance in a plurality of processes of a semiconductor wafer.
Also, in Japanese Unexamined Patent Publication No. 4-106460 (related art 2) is disclosed a defect detecting technology for calculating the quantity of feature of the same image to be inspected by two different kinds of parameters, identifying objective defects, detecting defects identified in common by two kinds of parameters to thereby eliminate the duplication of detection of the defects.
In this connection, since a circuit pattern formed on a semiconductor device is becoming more microscopic, foreign particles, circuit pattern defects, and scratches which are required to be detected by inspection are growing more microscopic.
Further, a semiconductor is manufactured through a very large number of manufacturing processes. Therefore, an inspection apparatus needs to be applied to a semiconductor wafer manufactured through various manufacturing processes. However, the condition of the surface (underlying layer) of the semiconductor wafer manufactured through various manufacturing processes varies variously. In this manner, the inspection apparatus needs to detect particles to be detected such as foreign particles, circuit pattern defects, and the scratches, which are growing more microscopic, from the variously changing surface of the semiconductor wafer. Therefore, it is necessary to optimize subtle inspection conditions.
However, it is difficult to form bumps and dips equivalent to foreign particles and defects on the surface having variously changing conditions as a test sample for calibration and hence the above-mentioned related arts have a problem that it is difficult to set a proper inspection condition by the use of a test sample for calibration.